<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        //符号比较大小 
        var a = 10
        var b = 20
        console.log(b>=a);//true
        console.log(b<a);//false
        // ==   ===
        var c = '20'
        console.log(b==a);//false  两个等号才表示等于
        console.log(b===c);//false 三个等号表示值和属性都相等
       //!=  表示值不相等
       //!== 表示值和属性全部都不相等
    </script>
</body>
</html>